http://www.evcomponents.com/SearchResults.asp?Cat=33 Was the cheapest place I've found batteries, but they seem to have changed things around when I wasn't looking...Their 200ah Blue Sky LFP4 pack was like $200 or so, and since I'll be throwing the numbers around for the 3+ years it'll take me to save up, lol...it would put your battery pack cost up around $7k or so, for like 72V @540 amp draw, and double that for 144V, but you would also have insane range and reasonable (possibly great) acceleration, depending on the rest of your setup. I'll be watching these prices anyway, and have been digging around some of the more interesting places for info/parts given some possible project ideas I have. Seriously, though, 144v + 540 amp (c3 draw on these) would be 77kw for an OK draw...hehe, plus 2000 charge cycles is like 5.5 years, if your run it every day! Lead acid is only cheaper initially, but since I have to save up to begin with, I'm not going to bother unless I fall into like half the pieces lol!